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I'm not a designer, but to my non-professional eyes this looks good.

Do you think this font would be a good choice for a text editor?

I'd stick to monospace fonts for text editors

Even if it's a SaaS app for general writing, not a code editor? (I guess I should've clarified this right away)

This supports being monospaced by the looks of it - scroll down to the tabular data feature. The font really has a wide variety of options.

It's tabular numbers only, not letters.

And "automatically monospacing" any font that is designed proportionally will look terrible, so stick to an entirely monospace font.